Published on January 31st, 2012 | by Zachary Shahan3
Luminescent Solar Concentrator Efficiency Improvement from UC-Merced Researchers
First of all, if you want an intro on luminescent solar concentrators (as I did), check out that Wikipedia page linked above.
Now, the important news is that a team of researchers at the University of California, Merced (UC Merced), has found a way to redesign luminescent solar concentrators in order to make them “more efficient at sending sunlight to solar cells.”
“We tweaked the traditional flat design for luminescent solar concentrators and made them into cylinders,” UC Merced physics professor Sayantani Ghosh, the lead researcher, said. “The results of this architectural redesign surprised us, as it significantly improves their efficiency.”
Luminescent Solar Concentrators’ Limitations
From the UC Merced news release: “The main problem preventing luminescent concentrators from being used commercially is that they have high rates of self-absorption, Ghosh said, meaning they absorb a significant amount of the light they produce instead of transporting it to the solar cells.”
That explains why most of us probably hadn’t heard about this technology until now.
Improving Efficiency with Hollow Cylindrical Design
But, as Ghosh noted above and UC Merced presents more specifically, the team found that “hollow cylinders absorb more sunlight while having lower self-absorption losses.”
Luminescent Solar Concentrator Advantages
As noted in the Wikipedia introduction on luminescent solar concentrators above, the main advantage of this solar technology is that it works better than traditional cells in diffuse sunlight, meaning that 1) these concentrators work better on cloudy days, and 2) they don’t need to face the sun directly and, thus, don’t require sun-tracking mechanisms.
Could These Be Commercially Viable?…
According to Ghosh, this discovery could make luminescent solar concentrators commercially viable. The new design improves performance without increasing the number of quantom dots needed, so the cost isn’t going to change much, if at all.
“This saves on infrastructure costs and also opens up the possibility that the collectors can be integrated onto vertical surfaces like walls and windows,” UC Merced writes. “The next step is to develop a large array of hollow cylindrical luminescent solar concentrators and track the efficiency of the panel.”
What Are Quantum Dots?
If you skipped the Wikipedia intro above, quantum dots are embedded in the concentrators and allow them to “absorb solar radiation over a broad range of colors and re-emit it over a narrower range,” UC Merced summarizes.
More on UC Merced’s Research
Other members of the research team included Richard Inman, Georgiy Shcherbatyuk, Dmitri Medvedko, and Ajay Gopinathan.
A paper on the work, “Cylindrical luminescent solar concentrators with near-infrared quantum dots,” has been published in the journal Optics Express.